Safety attachment for tanks



May 3, 1927. 5 1,626,721"

J. COHN SAFETY ATTACHMENT FOR TANKS Filed July 26, 1921 Jacob L'ohn 1 g l-M @H'om mp- Patented May 3, 1927.

Moon 00:11:, or new YORK, 1v. 2., nssreivoa'nv Mnsnn nssrenmnnrs, 'ro NON- EXPLOSIVE CORPORATION OF DELAWARE.

OF AMERICA (NEW COR3PORATION), A CORPORATION SAFETY ATTACHMENT FOR TAlSlKS.

Application filed July 26,

The present invention relates to improvements in safety attachments for tanks and has for an object to provide for the venting of excess pressure from the tank while also permitting; of the entry of airto relieve any partial vacuum forming in the tank as when drawing off the contents' The invention further contemplates the use of a counter balance structure in which vibration will be avoided and which will be accessible for adjustment on the exterior of the tank.

A further object of the invention contemplates. providing an enlarged bearing surface for the pressure relief valve in order to permit the relief valve to accommodate itself to its seat and thereby insure-a tight fit during the closing of the valve.

With theforegoing and other objects in view, the invention will be more fully described hereinafte'r, and will be more particularly pointed out in the claim appended hereto In the drawings, wherein like symbols refer to like or corresponding parts throughout the several views,

Figure 1 is a top plan view of a device constructed according to the present invention, and

Figure 2 is a side view thereof with parts shown in section.

Referring more particularly to the drawings 3 designates the tank wall provided with the threaded opening 4 to receive the bushing 5 which projects above and below the tank wall. The skirt portion 6 within the tank is adapted to receive the foraminous or reticulated cylinder composed preferably of a perforated metal 7 with wire mesh 8 on both sides thereof; or perforated metal may be placed on opposite sides of the central wire screen and the device is supported from the skirt as by pressing the metal into the annular groove 9 on the exterior thereof.

The upper projecting part of the bushing is provided with an elongated frusto-conical valve seat 10, the section of the cone on which the same is taken being inverted. The valve seat 10 cooperates with a complemental elongated and frusto-conical surface upon a hollow relief valve body 11 which.

extends above the bushing and is provided in its upper part with openings 12 through which air from the atmosphere freely passes 1924. Serial No. 728,337.

to the large interior space of the valve body.

The bottom portion of the valve body bethrough the cylindrical guide 16 carried cen-' trally within the relief valve body 11 and depending from the topthereof. The lower end of the guide cylinder 16 is closed by. a threaded plug 17 through which the valve stem 15 freely slides, and a plunger ,18 provided with air ports19 ismounted to reciprocate 1n the guide cylinder and secured to the upper end of the valve stem. The piston and guide cylinder form in effect a dash pot to prevent the chattering of the. valve and the plunger 18 subserves. the further functlon of acting asgan abutment for the upper end of the coil spring 20, the lower end of which bears against the plug 17. The function of this spring is to maintain the plunger in the raised position and the air valve 18 closed against-its seat 14.

The air valve is therefore carried by the relief valve body 11 and the two constitute a unitary structure. The accumulated pressure in the tank will act beneath the wide surface of the air valve 13 and will raise the relief valve from the seat 10 permitting of This unitary device is. counter balanced and to this end I provide'a rigid stud 21 projecting from and axially of the relief valve body 11.. The stud is adapted to reciprocate through a bearing 22 supported by the spider arms 23 which are secured as by means of the screws or other fastenings 24 to a flange 25 of the bushing 5 which flange also acts to compress a gasket 26 to avoid the leakage of pressure from the tank about the bushing threads. The upper end of the stud 21 is threaded to receive a cross head 27 provided with divergent forked arms 28 and 29 supthe escape of pressure while the atmosphere porting pins 31 which slide in the slots 31 of the counterweight levers 32. The slots open mutually toward one another upon the ends of the levers so as to permit the ready assembly of the parts. The levers 32 are fulcrumed as indicated at 33 upon the horns an which may be madev apart of the spider arms. The counter weights 35 slide upon the outer ends of the levers 32 and are threaded to engage the threaded adjusting rods 36. The adjusting rods are fixed against longitudinal movement in collars 37 upon the arms but they are free to rotate and on rotation thereof the weights are shifted either toward or from the pivot points 33 to vary the counter balancing action.

In the use of the device the parts are assembled upon the tank as shown in Figure 2, the entire assembly being upon the bushing which is secured into the opening in the tank wall. The springQO and counter balance weights are selected and adjusted to suit conditions of use, so that the relief and air valve will open upon the desired pressure. Any pressure accumulating within the tank will pass through the mesh and perforations of the safety cylinder and accumulating beneath the air valve will lift the relief valve and permit escape thereof, while the atmospheric air will be admitted through the air valve when a suitable degree of vacuum occurs in the tank. By adjusting the weights 35 the degree of pressure upon which the relief valve will open may be regulated and it will be understood that the stud 21 is rigid and partakes of a rectilinear movement through the bearing 22, so that the movement is directly transmitted to the lovers and no lost motion occurs and no lateral vibration may take place in this stud.

The enlarged valve surface permits the valve to accommodate itself to the wide area and to insure tight seating.

' It is obvious that various changes and modifications may be made in the details of construction and design of the above specifically described embodiment of this invention without departing from the spirit thereof, such changes and modifications being. restricted only by the scope of the following claim.

What is claimed is In combination with a receptacle, a relief valve, an air valve carried by said relief valve, a yoke member having horns detachably affixed to said receptacle, a rigid stud attached to the top of said relief valve and adapted toreciprocate in said yoke upon the movement of said relief valve, a cross head with divergent arms det-achably affixed to the top of said stud above the yoke, weighted levers fulcrumed at a point intermediate their ends to the horns of said yoke and hav ing the near ends thereof provided with slots opening through such ends, pins carried by said divergent arms slidably anddetachably engaged in said slots.

JACOB COHN. 

